Gavi, the Vaccine Alliance, and Merck have signed a purchase agreement worth $5 million to push the VSV-EBOV Ebola vaccine through initial licensing and to stockpile enough for clinical trials and emergency use.

The agreement between Gavi and Merck, which licensed the vaccine in 2014 to improve its chances of reaching clinical trials and of production ramp-up, was announced today at the World Economic Forum in Davos, Switzerland. The deal is unusual, because it signals Gavi's first such support for an unlicensed vaccine.

VSV-EBOV, one of several vaccines under development, is furthest along in clinical trials and after showing good effectiveness in a phase 3 trial has been used in ring vaccination strategies in the outbreak region. Developed by Canadian scientists, VSV-EBOV was licensed by NewLink Genetics along with Merck.

Path to licensing, stockpiling

As part of the deal, Merck will submit the vaccine for licensing by the end of 2017, and once it's approved, Gavi will start buying the vaccine to build a stockpile for future outbreaks. Also, Merck will ensure 300,000 doses of the vaccine are available as of May to use in expanded clinical trials or for emergency use.

In late December, Merck announced that the World Health Organization (WHO) had agreed to review an emergency use application for VSV-EBOV, which, once approved, would help pave the way for the experimental vaccine to be used in public health emergencies and for United Nations agencies to buy the vaccine.

Seth Berkley, MD, Gavi's chief executive officer, said in the statement that the suffering caused by the Ebola outbreak was a wake-up call to the global health community. "New threats require smart solutions, and our innovating financing agreement with Merck will ensure that we are ahead of the curve for future Ebola outbreaks."

Merck's Julie Gerberding, MD, MPH, executive vice president for strategic communications, global public policy, and population health, said in the statement, "We applaud Gavi for this bold step to be part of the solution to address a disease that has impacted so many lives." Gerberding is former director of the US Centers for Disease Control and Prevention.

Gavi had committed funding for Ebola vaccine purchase in December 2014 and is working with all vaccine makers that are developing Ebola vaccines, including GlaxoSmithKline and Johnson & Johnson.

Experts applaud step, call for sustainability

Jeremy Farrar, MD, PhD, director of the Wellcome Trust, said in the statement that impressive results for the VSV-EBOV vaccine and promising progress on others is one of the few bright spots to come out of the outbreak.

He added that he's delighted that Gavi has committed to the next push toward licensure, the ultimate goal to make it available to those who need it. "It should also give others working in this space the confidence needed to carry on pursuing alternative vaccines," Farrar added.

Michael Osterholm, PhD, MPH, director of the University of Minnesota's Center for Infectious Disease Research and Policy (CIDRAP), told CIDRAP News that today's announcement is a major incentive to get the vaccine licensed and approved, and he applauded Gavi for going ahead with the plan before VSV-EBOV is licensed. CIDRAP is publisher of CIDRAP News.

However, he said more work is needed to move forward with other vaccines and to devise a sustainable business model for Ebola vaccines. Osterholm said $5 million is not enough to spur companies to make major investments in them.

Wellcome Trust and CIDRAP led an expert team (Team B) that reviewed the Ebola vaccine development landscape. Last February Team B released a report recommending that clinical trials continue because of the long-term threat in Africa, even if cases decline and make effectiveness assessments difficult. The 26-member team also recommended that several candidate vaccines be tested, since more than one type might be needed.